KR101718359B1 - Method of aligning a substrate and apparatus for performing the same - Google Patents

Abstract

According to the substrate alignment method, the first alignment mark and the second alignment mark positioned in the first shot region on the substrate are sequentially recognized. The substrate is first aligned using any one of the first alignment marks and the first alignment marks recognized first among the second alignment marks. Sequentially recognizing an alignment mark used in the primary alignment of the substrate and an unused alignment mark among the first alignment mark and the second alignment mark positioned in the second shot area on the substrate. The substrate is secondarily aligned using an alignment mark used in the primary alignment of the substrate and one of the alignment marks recognized in the unused alignment mark. Therefore, the time required for recognizing the alignment mark can be shortened.

Description

Field of the Invention [0001] The present invention relates to a substrate alignment method,

The present invention relates to a substrate alignment method and apparatus for performing the same, and more particularly, to a method of aligning a patterned semiconductor substrate and an apparatus for performing such a method.

Generally, various semiconductor processes are performed on a semiconductor substrate to form a plurality of patterns. Further, in order to confirm whether or not the patterns are defective, a process of inspecting the patterns between the respective processes is performed.

Here, in order to inspect the pattern, the process of accurately aligning the semiconductor substrate should be given priority. The alignment method includes a step of moving the semiconductor substrate so that the alignment mark formed on the scribe lane of the semiconductor substrate coincides with a predetermined coordinate in the alignment device.

According to the conventional alignment method, the first alignment mark located in the first shot area (shot) is recognized, and the recognized first alignment mark is matched with the set first coordinate. Next, the second alignment mark in the second shot area located in the x-axis direction from the first shot area is recognized, and the recognized second alignment mark is matched with the predetermined second coordinate. Then, the third alignment mark in the third shot area located in the y-axis direction from the first shot area is recognized, and the recognized third alignment mark is matched with the predetermined third coordinate. That is, the conventional method matches one alignment mark located within each shot area with predetermined coordinates.

On the other hand, if the alignment mark is not recognized, the alignment device will determine alignment error for the semiconductor substrate. The semiconductor substrate determined as an alignment error is taken out of the alignment apparatus. After setting the new alignment condition in the alignment apparatus, the semiconductor substrate is aligned by performing the above-described processes for the semiconductor substrate.

Here, although the alignment mark coincides with the predetermined coordinates, there are cases where the alignment device does not recognize the alignment mark due to factors such as a bright image of the alignment mark and the like. According to the conventional method, even in this case, the aligning device is determined to be misaligned with respect to the semiconductor substrate. As a result, the time required for the alignment process is considerably increased, which is a factor for significantly lowering the yield of the semiconductor device.

In the past, only one alignment limit value was set as a criterion for determining alignment errors. If the alignment value indicated by the recognized alignment mark is greater than or equal to the alignment limit value, alignment is determined to be normal. On the other hand, if the alignment value indicated by the recognized alignment mark is less than the alignment limit value, it is determined to be an alignment error. Because of this, although the semiconductor substrate is accurately aligned, the alignment value of the alignment mark may appear to be less than the alignment limit value due to the clear image of the alignment mark. According to the conventional method, an alignment error is determined for the semiconductor substrate even in such a case.

In order to solve such a determination error, a method of aligning the substrate using any one of a plurality of alignment marks located within one shot region on the substrate has been proposed. If any one alignment mark in one shot area is not recognized, another alignment mark in the shot area is recognized, so that it is possible to prevent a phenomenon that a correctly aligned substrate is determined as an alignment error.

However, the conventional method recognizes the alignment marks in order in the preceding shot area when performing the alignment process for the subsequent shot area. That is, regardless of the alignment marks recognized in the preceding shot area, the alignment marks are recognized in a predetermined order with respect to the subsequent shot area. For example, if the third alignment mark is recognized in the preceding shot area, the first alignment mark and the second alignment mark are recognized first even if the third alignment mark is likely to be recognized first in the subsequent shot area, The third alignment mark is recognized.

This has the disadvantage that it takes a long time to recognize the alignment mark. As a result, there is a problem that the time required for aligning the substrate is increased, and the yield of the semiconductor device is lowered.

The present invention provides a method for rapidly aligning a substrate.

The present invention also provides an apparatus for performing the above-described method.

According to the substrate alignment method according to one aspect of the present invention, the first alignment mark and the second alignment mark positioned in the first shot region on the substrate are sequentially recognized. The substrate is first aligned using any one of the first alignment marks and the first alignment marks recognized first among the second alignment marks. Sequentially recognizing an alignment mark used in the primary alignment of the substrate and an unused alignment mark among the first alignment mark and the second alignment mark positioned in the second shot area on the substrate. The substrate is secondarily aligned using an alignment mark used in the primary alignment of the substrate and one of the alignment marks recognized in the unused alignment mark.

According to an embodiment of the present invention, the first alignment mark may have a higher sharpness than the second alignment mark.

According to another embodiment of the present invention, the method of defragmenting is characterized in that the alignment marks used in the secondary alignment of the substrate among the first alignment marks and the second alignment marks located in the third shot area on the substrate, And sequentially aligning the substrate with an alignment mark used in the secondary alignment of the substrate and any alignment mark recognized first of the unused alignment marks can do. The second shot area may be located in a first direction from the first shot area, and the third shot area may be positioned in a second direction perpendicular to the first direction.

According to another embodiment of the present invention, the alignment method may further include displaying alignment values indicating alignment states of the first alignment mark and the second alignment mark.

According to another embodiment of the present invention, the alignment method may further include setting an allowable alignment score for determining the non-recognition of the first alignment mark and the second alignment mark. The alignment method may further include setting a final alignment limit value that is lower than the alignment limit value to finally determine the non-recognition of the one alignment mark and the second alignment mark. The step of setting the final alignment limit value may include changing the alignment value in descending order from the alignment limit value to the final alignment limit value.

According to another embodiment of the present invention, the alignment method may further include correcting the height of the substrate.

According to another aspect of the present invention, there is provided a method of aligning a substrate, comprising: forming a first alignment mark having a first sharpness located in a first shot region on a substrate, a second alignment mark having a second sharpness, A third alignment mark having a third sharpness lower than the second sharpness, and a fourth alignment mark having a fourth sharpness lower than the third sharpness. The substrate is first aligned using any one of the first alignment mark, the second alignment mark, the third alignment mark, and the first alignment mark recognized first among the fourth alignment marks. The alignment marks used in the first alignment of the substrate among the first alignment mark, the second alignment mark, the third alignment mark, and the fourth alignment mark positioned in the second shot area on the substrate. If the alignment mark used in the first alignment of the substrate is not recognized, the remaining alignment marks except for the alignment mark used in the first alignment of the substrate are sequentially recognized in the order of sharpness. The substrate is secondarily aligned using any one of the first alignment marks, the second alignment marks, the third alignment marks, and the fourth alignment marks recognized in the second shot area. The alignment marks used in the secondary alignment of the substrate among the first alignment mark, the second alignment mark, the third alignment mark and the fourth alignment mark positioned in the third shot area on the substrate. When the alignment mark used in the second alignment of the substrate is not recognized, the remaining alignment marks except for the alignment mark used in the second alignment of the substrate are sequentially recognized in the order of sharpness. The substrate is tertiary aligned using any one of the first alignment marks, the second alignment marks, the third alignment marks, and the fourth alignment marks recognized in the third shot area.

According to an embodiment of the present invention, the alignment method further includes the step of displaying alignment values indicating alignment states of the first alignment mark, the second alignment mark, the third alignment mark and the fourth alignment mark can do.

According to another embodiment of the present invention, the alignment method includes an allowable alignment score for determining the non-recognition of the first alignment mark, the second alignment mark, the third alignment mark, and the fourth alignment mark, And a step of setting The method may further include setting a final alignment limit value that is lower than the alignment limit value to finally determine the uninformed expression of the first alignment mark, the second alignment mark, the third alignment mark, and the fourth alignment mark As shown in FIG. The step of setting the final alignment limit value may include changing the alignment value in descending order from the alignment limit value to the final alignment limit value.

A substrate alignment apparatus according to another aspect of the present invention includes a recognition unit, a determination unit, and an alignment unit. The recognition unit is disposed above the stage on which the substrate is placed to recognize at least two alignment marks located within each shot region on the substrate in the order of sharpness of the alignment marks using the coordinates of predetermined alignment marks . Further, the recognition unit first recognizes any one of the alignment marks recognized in the preceding shot area in the subsequent shot area. The determination unit determines whether or not the alignment marks recognized by the recognition unit are aligned. The alignment unit moves the stage so that the position of the alignment mark recognized by the recognition unit coincides with the coordinates.

According to an embodiment of the present invention, the recognition unit may include a display unit for displaying an alignment value indicating an alignment state of the alignment marks.

According to another embodiment of the present invention, the determination unit sets a final alignment limit value that is lower than the alignment limit value for determining the non-recognition of the alignment marks and the alignment limit value to finally determine the non-recognition of the alignment marks For example.

According to another embodiment of the present invention, the aligning unit may include a horizontal driving unit for moving the stage in the horizontal direction, and a vertical driving unit for moving the stage in the vertical direction.

According to the present invention as described above, since the alignment mark recognized first in the preceding shot area is first recognized in the subsequent shot area, the time required to recognize the alignment mark can be shortened. In addition, if recognition of the alignment mark recognized first in the preceding shot area fails in the subsequent shot area, the remaining alignment marks are recognized in the order of sharpness, so that the alignment mark recognition time is reduced. As a result, the time required for aligning the substrate can be greatly shortened, and the yield of manufacturing the semiconductor device can be improved.

1 is a block diagram showing a substrate alignment apparatus according to an embodiment of the present invention.
Fig. 2 is a plan view showing a substrate on which the positions of alignment marks are indicated. Fig.
FIGS. 3 to 6 are flowcharts sequentially illustrating a method of aligning a substrate using the apparatus of FIG.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The present invention is capable of various modifications and various forms, and specific embodiments are illustrated in the drawings and described in detail in the text. It should be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. Like reference numerals are used for like elements in describing each drawing.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, the terms "comprises", "having", and the like are used to specify that a feature, a number, a step, an operation, an element, a part or a combination thereof is described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

Substrate alignment device

FIG. 1 is a block diagram showing a substrate alignment apparatus according to an embodiment of the present invention, and FIG. 2 is a plan view showing a substrate on which positions of alignment marks are indicated.

1 and 2, the substrate aligning apparatus 300 according to the present embodiment includes a recognition unit 310, a determination unit 320, and an alignment unit 330. [

The substrate W placed on the stage is divided into a plurality of shot areas. At least two alignment marks (M1, M2, M3, M4) are formed in each shot area in this embodiment. The first to fourth alignment marks M1, M2, M3, and M4 have different shapes. In addition, the first alignment mark M1 has a first sharpness. The second alignment mark M2 has a second sharpness lower than the first sharpness. The third alignment mark M3 has a third sharpness lower than the second sharpness. The fourth alignment mark M4 has a fourth sharpness lower than the third sharpness. That is, the first alignment mark M1 has the highest sharpness and the fourth alignment mark M4 has the lowest sharpness.

The recognition unit 310 is disposed at the top of the stage. The recognition unit 310 sequentially recognizes the first to fourth alignment marks M1, M2, M3, and M4 in the order of definition in each shot area. In addition, the coordinates of the alignment marks are input to the recognition unit 310. [ Therefore, the recognition unit 310 recognizes the alignment mark depending on whether or not the alignment mark is located on the input coordinates.

In this embodiment, the recognition unit 310 first recognizes the first alignment mark M1 in the first shot area S1. If the first alignment mark M1 is not recognized, the recognition unit 310 recognizes the second alignment mark M2 in the first shot area S1. If the second alignment mark M2 is not recognized, the recognition unit 310 recognizes the third alignment mark M3 in the first shot area S1. If the third alignment mark M3 is not recognized, the recognition unit 310 recognizes the fourth alignment mark M4 in the first shot area S1.

When any one of the first to fourth alignment marks M1, M2, M3, and M4 is recognized, the recognition unit 310 recognizes the second shot area S2 positioned in the first direction from the first shot area S1, Recognizes the recognized alignment mark located in the first position. For example, the first and second alignment marks M1, M2 in the first shot area S1 may not have the correct shape due to process errors. In this case, a third alignment mark M3 having a lower sharpness than the first and second alignment marks M1 and M2 may be recognized. In particular, the first and second alignment marks M1 and M2 may not have an accurate shape even in another shot area.

Accordingly, when the recognition unit 310 sequentially recognizes the first to fourth alignment marks M1, M2, M3, and M4 in the second shot area S2 in order of clarity, the recognition unit 310 recognizes the first And the second alignment marks M1 and M2, and recognizes the third alignment mark M3. As a result, unnecessary time for the recognition unit 310 to recognize the first and second alignment marks M1 and M2 can be wasted.

In the present embodiment, when the recognition unit 310 recognizes the third alignment mark M3 in the first shot area S1, the recognition unit 310 recognizes the third alignment mark M3 in the second shot area S2 ) Is recognized first. Accordingly, it is possible to reduce the time for the recognition unit 310 to recognize the first and second alignment marks M1 and M2 in the second shot area S2.

If the recognition unit 310 does not recognize the third alignment mark M3 in the second shot area S2, the recognition unit 310 does not recognize the fourth alignment mark M4, And sequentially recognizes the alignment marks M1, M2, and M4. That is, the recognition unit 310 sequentially recognizes the first alignment mark M1, the second alignment mark M2, and the fourth alignment mark M4 in order of high clarity. Therefore, since the recognition unit 310 sequentially recognizes the alignment marks M1, M2, M3, and M4 in the order of sharpness, the recognition unit 310 recognizes any one of the alignment marks M1, M2, M3, and M4 It is possible to shorten the time required for recognition.

When the recognition unit 310 recognizes the second alignment mark M2 in the second shot area S2, the recognition unit 310 gives priority to the second alignment mark M2 in the third shot area S3 . When the recognition of the second alignment mark M2 fails, the recognition unit 310 recognizes the first alignment mark M1, the third alignment mark M3 and the fourth alignment mark M4 in the order of sharpness. In this embodiment, the third shot area S3 is located in the second direction substantially orthogonal to the first direction.

In the present embodiment, the recognition unit 310 sequentially recognizes four alignment marks in one shot area. However, the recognition unit 310 may recognize two, three, or more than five alignment marks in one shot area.

In addition, the recognition unit 310 includes a display unit 312 for displaying an alignment value numerically indicating the alignment status of the alignment marks. The display unit 312 displays the alignment value of the alignment mark in real time while the recognition unit 310 recognizes the alignment mark. Therefore, the inspector can see the alignment value displayed on the display unit 312 and can immediately know the alignment status of the alignment mark. Here, the alignment value is a value indicating the degree to which the recognition unit 310 recognizes the shape of the alignment mark. Therefore, as the alignment mark becomes clearer, a higher alignment value will be displayed on the display unit 312. [

The determination unit 320 determines whether the alignment marks are aligned according to the alignment value. Accordingly, the determination unit 320 includes an input unit 322 for setting an alignment limit value as a reference for determining whether the alignment marks are aligned. A final alignment limit value for finally determining whether the alignment marks are aligned through the input unit 322 is set. The final alignment limit value is lower than the alignment limit value.

Here, if the alignment limit value is too high, a large number of substrates will be determined to be misaligned due to the unclearness of the alignment mark, even though they are aligned correctly. On the other hand, if the alignment limit value is too low, not correctly aligned substrates will also be determined to be aligned. Accordingly, the alignment limit value can be set optimally through alignment tests on a plurality of substrates.

On the other hand, patterns having a shape similar to an alignment mark may exist on the substrate. These patterns may be located adjacent to the alignment mark. In this case, the recognition unit 310 may recognize the pattern, not the alignment mark. The shape of the pattern is similar to the alignment mark, but it is not the same as the alignment mark, so the alignment value of the pattern will be lower than the alignment value of the alignment mark.

The final alignment limit value is used in order to determine that alignment is normal when a non-bright alignment mark is recognized and to determine misalignment when a pattern is recognized. Specifically, the alignment value of the non-bright alignment mark will be lower than the alignment limit value. Thus, the determination unit 320 determines once misalignment with respect to a non-bright alignment mark. Then, through the input unit 322, alignment values of the alignment marks and patterns are checked while changing the alignment limit values from the preset alignment limit values in descending order. Then, since the alignment value of the non-bright alignment mark is higher than the alignment value of the pattern, if the non-bright alignment mark is recognized, the alignment is determined to be normal, and when the pattern is recognized, the alignment value to determine misalignment can be confirmed. These alignment values correspond to the final alignment limit values. The final alignment limit value can be set optimally through alignment processes for a plurality of substrates as well as alignment limit values.

The aligning unit 330 moves the stage so that the alignment mark coincides with the preset coordinates according to the determination result of the determination unit 320. [ Accordingly, the alignment unit 330 includes a horizontal driving unit 332 for moving the stage along the horizontal direction.

Here, there may be a height difference between alignment marks. Therefore, if the distance between the stage and the recognition unit 310 is always constant, the recognition unit 310 may not recognize the alignment mark because the focus between the recognition unit 310 and the alignment mark is inconsistent. For focus alignment between the recognition unit 310 and the alignment mark, the alignment unit 330 may include a vertical driver 334 for moving the stage along the vertical direction.

Board alignment method

FIGS. 3 to 6 are flowcharts sequentially illustrating a method of aligning a substrate using the apparatus of FIG.

Referring to FIGS. 1 and 3, in step ST410, an alignment limit value is set in the determination unit 320 through the input unit 322. FIG.

In step ST420, a final alignment limit value is set in the determination unit 320 through the input unit 322. [

In this embodiment, the first to fourth alignment marks M1, M2, M3, and M4 have different shapes. In addition, the first to fourth alignment marks M1, M2, M3, and M4 have different sharpnesses. Specifically, the first alignment mark M1 has a first sharpness. The second alignment mark M2 has a second sharpness lower than the first sharpness. The third alignment mark M3 has a third sharpness lower than the second sharpness. The fourth alignment mark M4 has a fourth sharpness lower than the third sharpness. That is, the first alignment mark M1 has the highest sharpness and the fourth alignment mark M4 has the lowest sharpness. Therefore, four alignment limit values and four final alignment limit values respectively corresponding to the respective shapes of the first to fourth alignment marks M1, M2, M3, and M4 will be set in the determination unit 320. [

In step ST430, the recognition unit 310 sequentially recognizes the first to fourth alignment marks M1, M2, M3, and M4 located in the first shot area S1 in the order of sharpness. Specifically, it is checked whether or not the first alignment index of the first alignment mark M1 is equal to or greater than the alignment limit value. If the first alignment index is equal to or larger than the alignment limit value, in step ST440, the determination unit 320 determines that the first alignment mark M1 is recognized.

On the other hand, if the first alignment index is less than the alignment limit value, it is checked in step ST440 if the first alignment index is equal to or greater than the final alignment limit value. If the first alignment index is greater than or equal to the final alignment limit value, in step ST470, the determination unit 320 determines that the first alignment mark M1 is recognized.

However, if the first alignment index is less than the final alignment limit value, then in step ST450, the vertical drive 334 of the alignment unit 330 selectively lifts the stage along the vertical direction, Thereby matching the focal points of the marks M1.

After the stage is moved, in step ST460, it is finally confirmed whether the first alignment index is equal to or greater than the final alignment limit value. If the first alignment index is greater than or equal to the final alignment limit value, then in step ST470, the determination unit 320 finally determines that the first alignment mark M1 has been recognized. Through such a method, it is possible to judge recognition when a clear alignment mark is detected, whereas when it is detected that a pattern similar to an alignment mark is detected, it can be judged to be non-recognition.

In step ST480, the horizontal driving unit 332 of the alignment unit 330 aligns the substrate by moving the stage along the horizontal direction so that the first alignment mark M1 recognized and the predetermined coordinate are aligned.

On the other hand, if the first alignment index is less than the final alignment limit value, in step ST490, the determination unit 120 finally determines that the first alignment mark M1 is not recognized.

If it is determined that the recognition of the first alignment mark M1 is unsuccessful, the above-described processes are sequentially performed on the second alignment mark M2, the third alignment mark M3, and the fourth alignment mark M4.

Specifically, referring to Figs. 1 and 4, in step ST510, the recognition unit 310 recognizes the first alignment mark M1 in the first shot area S1.

When the first alignment mark M1 is recognized, in step ST520, the aligning unit 330 first aligns the substrate using the first alignment mark M1.

If the first alignment mark M1 is not recognized, in step ST530, the recognition unit 310 recognizes the second alignment mark M2 in the first shot area S1.

When the second alignment mark M2 is recognized, in step ST540, the aligning unit 330 secondary aligns the substrate using the second alignment mark M2.

If the second alignment mark M2 is not recognized, the recognition unit 310 recognizes the third alignment mark M3 in the first shot area S1 at step ST550.

When the third alignment mark M3 is recognized, in step ST560, the alignment unit 330 third aligns the substrate using the third alignment mark M3.

Here, in this embodiment, it is exemplified that the third alignment mark M3 in the first shot area S1 is recognized. If the third alignment mark M3 is not recognized, the recognition unit 310 will recognize the fourth alignment mark M4.

Referring to FIGS. 1 and 5, in step ST570, the recognition unit 310 first recognizes the third alignment mark M3 in the second shot area S2. That is, the third recognition mark M3 recognized first in the first shot area S1 is first recognized in the second shot area S2.

When the third alignment mark M3 is recognized, in step ST580, the aligning unit 330 secondary aligns the substrate using the third alignment mark M3.

If the third alignment mark M3 is not recognized, the recognition unit 310 recognizes the first alignment mark M1 in the second shot area S2 in step ST590. That is, in the subsequent shot area, when the first recognized alignment mark is not recognized, the alignment marks are sequentially recognized in the order of sharpness.

When the first alignment mark M1 is recognized, in step ST600, the alignment unit 330 secondary aligns the substrate using the first alignment mark M1.

If the first alignment mark M1 is not recognized, in step ST610, the recognition unit 310 recognizes the second alignment mark M2 in the second shot area S2.

When the second alignment mark M2 is recognized, in step ST620, the aligning unit 330 second aligns the substrate using the second alignment mark M2.

Here, in the present embodiment, it is exemplified that the second alignment mark M2 in the second shot area S2 is recognized. If the second alignment mark M2 is not recognized, the recognition unit 310 will recognize the fourth alignment mark M4.

Referring to FIGS. 1 and 6, in step ST630, the recognition unit 310 first recognizes the second alignment mark M2 in the third shot area S3. That is, the second alignment mark M2 recognized first in the second shot area S2 is first recognized in the third shot area S3.

When the second alignment mark M2 is recognized, in step ST640, the alignment unit 330 tertiary-aligns the substrate using the second alignment mark M2.

If the second alignment mark M2 is not recognized, in step ST650, the recognition unit 310 recognizes the first alignment mark M1 in the third shot area S3.

When the first alignment mark M1 is recognized, in step ST660, the alignment unit 330 tertiary-aligns the substrate using the first alignment mark M1.

If the first alignment mark M1 is not recognized, in step ST670, the recognition unit 310 recognizes the third alignment mark M3 in the third shot area S3.

When the third alignment mark M3 is recognized, in step ST680, the aligning unit 330 third aligns the substrate using the third alignment mark M3. If the third alignment mark M3 is not recognized, the recognition unit 310 will recognize the fourth alignment mark M4.

As described above, according to the preferred embodiment of the present invention, since the alignment mark recognized first in the preceding shot area is first recognized in the subsequent shot area, the time required to recognize the alignment mark can be shortened. In addition, if recognition of the alignment mark recognized first in the preceding shot area fails in the subsequent shot area, the remaining alignment marks are recognized in the order of sharpness, so that the alignment mark recognition time is reduced. As a result, the time required for aligning the substrate can be greatly shortened, and the yield of manufacturing the semiconductor device can be improved.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention as defined by the following claims. It can be understood that it is possible.

310; Recognition unit 320; Determination unit
3330; Alignment unit

Claims (14)

delete delete delete delete delete delete delete A first alignment mark having a first sharpness positioned within a first shot region on the substrate, a second alignment mark having a second sharpness lower than the first sharpness, a second alignment mark having a third sharpness lower than the second sharpness, 3 alignment marks, and a fourth alignment mark having a fourth sharpness lower than the third sharpness, sequentially from an alignment mark having a high definition;
First aligning the substrate using any one of the first alignment marks, the second alignment marks, the third alignment marks, and the first alignment marks recognized first among the fourth alignment marks;
Recognizing an alignment mark used in the primary alignment of the substrate among the first alignment mark, the second alignment mark, the third alignment mark, and the fourth alignment mark positioned in the second shot area on the substrate;
Wherein when the alignment mark used in the first alignment of the substrate is not recognized, alignment marks other than the alignment mark used in the first alignment of the substrate among the first to fourth alignment marks in the second shot area Sequentially recognizing the alignment marks having high sharpness;
Second aligning the substrate using any one of the first alignment marks, the second alignment marks, the third alignment marks and the fourth alignment marks recognized in the second shot area, ;
Recognizing an alignment mark used in secondary alignment of the substrate among the first alignment mark, the second alignment mark, the third alignment mark, and the fourth alignment mark positioned in a third shot area on the substrate;
Wherein when the alignment mark used in the second alignment of the substrate is not recognized, alignment marks other than the alignment mark used in the second alignment of the substrate among the first through fourth alignment marks in the third shot area Sequentially recognizing the alignment marks having high sharpness;
Ordering the substrate using any one of the first alignment marks, the second alignment marks, the third alignment marks, and the fourth alignment marks recognized in the third shot area, ≪ / RTI > The substrate is placed on top of the stage on which the substrate is placed so that at least two alignment marks located within each shot region on the substrate are sequentially recognized from alignment marks having high definition using the coordinates of preset alignment marks, A recognizing unit which first recognizes any one of the alignment marks recognized first in the shot area in the subsequent shot area;
A determination unit for determining whether or not the alignment marks recognized by the recognition unit are aligned;
And an alignment unit for moving the stage so that the position of the alignment mark recognized by the recognition unit matches the coordinate. 10. The apparatus of claim 9, wherein the recognizing unit comprises a display unit for displaying an alignment value indicative of an alignment state of the alignment marks, the determination unit comprising an alignment limit value for determining the uninformedness of the alignment marks, And an input for setting a final alignment limit value that is lower than the alignment limit value to finally determine the non-recognition. 9. The method of claim 8, further comprising displaying alignment values representing alignment states of the first alignment mark, the second alignment mark, the third alignment mark, and the fourth alignment mark. Way. 9. The method of claim 8, further comprising setting an allowable alignment score for determining the non-recognition of the first alignment mark, the second alignment mark, the third alignment mark, and the fourth alignment mark And the substrate is aligned. 13. The method of claim 12, further comprising: setting a final alignment limit value that is lower than the alignment limit value to ultimately determine the non-recognition of the first alignment mark, the second alignment mark, the third alignment mark, ≪ / RTI > further comprising the step of: 14. The method of claim 13, wherein setting the final alignment limit value comprises changing the alignment value in descending order from the alignment limit value to the final alignment limit value.

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